WirelessHD is an industry-led effort to define a specification for the next generation wireless digital network interface for wireless high-definition signal transmission for consumer electronics products. The consortium currently has over 40 adopters; key members behind the specification include Broadcom, Intel, LG, Panasonic, NEC, Samsung, SiBEAM, Sony, Philips and Toshiba. The founders intend the technology to be used for the CE devices, PCs, and portable devices alike. The specification was finalized in January 2008.
Technology
The WirelessHD specification is based on a 7 GHz channel in the 60 GHz Extremely High Frequency radio band. It allows for uncompressed digital transmission of high-definition video and audio and data signals, essentially making it equivalent of a wireless HDMI. First-generation implementation achieves data rates from 4 Gbit/s, but the core technology allows theoretical data rates as high as 25 Gbit/s (compared to 10.2 Gbit/s for HDMI 1.3 and 21.6 Gbit/s for DisplayPort 1.2), permitting WirelessHD to scale to higher resolutions, color depth, and range.
The 60 GHz band usually requires line of sight between transmitter and receiver, and the WirelessHD specification ameliorates this limitation through the use of beam forming at the receiver and transmitter antennas to increase the signal's effective radiated power. The goal range for the first products will be in-room, point-to-point, non line-of-sight (NLOS) at up to 10 meters. The atmospheric absorption of 60 GHz energy by oxygen molecules limits undesired propagation over long distances and helps control intersystem interference and long distance reception, which is a concern to video copyright owners.
The WirelessHD specification has provisions for content encryption via Digital Transmission Content Protection (DTCP) as well as provisions for network management. A standard remote control allows users to control the WirelessHD devices and choose which device will act as the source for the display.
Promoters
* Broadcom Corporation
* Intel Corporation
* LG Electronics Inc.
* Panasonic Corporation
* Philips Electronics
* NEC Corporation
* Samsung Electronics, Co., Ltd
* SiBEAM, Inc.
* Sony Corporation
* Toshiba Corporation
Competition
* Wireless Gigabit Alliance (WiGig) promotes a different specification for multi-gigabit wireless communications operating over the same unlicensed 60 GHz spectrum.
* Wireless Home Digital Interface (WHDI) specification uses 20 or 40 MHz channels the 5 GHz unlicensed band, offering lossless video and achieving equivalent video data rates of up to 1.5 or 3 Gbit/s.
No comments:
Post a Comment